秦岭近邻地区秋季暴雨的天气动力学分析  

Synoptic analysis of rainstorm near Qinling mountain in autumn

作　　者：方建刚[1] 侯建忠[2] 陶建玲[2] 郭大梅[2] 

机构地区：[1]陕西省气候中心 [2]陕西省气象台,陕西西安710014

出　　处：《兰州大学学报（自然科学版）》2007年第4期31-36,共6页Journal of Lanzhou University(Natural Sciences)

基　　金：国家"973"项目(2004CB720208);中国科学院知识创新项目(KZCX3-SW-339);科技部重大基础研究专项(2003CCC01500);陕西省气象局科技创新基金项目(2006-15)资助.

摘　　要：对2005年10月1～2日秦岭近邻地区连阴雨中的暴雨天气的成因进行分析,结果表明:暴雨发生在500 hPa东亚稳定的东高低环流形势下;低空西南急流为雨区提供了大量热量、动量及水汽,而高、低空急流的次级环流以及锋面次级环流之间的耦合加大了低层辐合和高层辐散,使暴雨区产生了强烈上升运动,为产生暴雨的中-α尺度系统形成提供了有利的大尺度环流背景场,秦巴山区复杂地形对产生暴雨中-α尺度的形成和发展也有一定的激发作用;螺旋度强度变化对暴雨发生发展有一定的指示意义,暴雨发生前对流中底层有较大螺旋度值,且呈下正上负的垂直结构,暴雨一般发生在对流层低层螺旋度正值中心的前方.The cause of rainstorm during successively overcast and rainy weather in 1-2 October 2005 was analyzed. The result showed that the rainstorm occurred at a stable circulation system with high pressure in the east and low pressure in the west of east Asia. The low level south-west jet stream supported enough heat, momentum and water vapor; the coupling of the second circulation of the upper level, low level and front enhanced the convergence at the low level and divergence at the upper level, and also provided the advantageous condition for the formation of meso-α. And the complex landform in Qinling Mountains also caused the development of meso-α. The occurrence of rain storm had some relation with the variation of the intensity of the spiral structure.

关 键 词：暴雨 急流 高低空急流耦合 螺旋度 

分 类 号：P458.1[天文地球—大气科学及气象学]